Mega Millions Payout Calculator - After-Tax Comparison

Mega Millions advertises a jackpot that is usually paid as a 30-year annuity unless the winner chooses a cash lump sum. The lump sum is smaller than the advertised annuity total because it is the present value of those future payments. This calculator uses a planning shortcut: the lump-sum gross prize is 60 percent of the entered jackpot, then divided by the number of winners. The annuity option uses the full jackpot divided by winners. Those conventions are educational, not the lottery’s official cash-option quote, which changes with interest rates. After the gross share is set, estimated tax is gross × (federal rate + state rate) / 100. After-tax payout is gross minus that tax. The tax model is a flat combined rate. Real lottery withholding, the federal supplemental rate, state residency rules, and later true-up on a tax return can all differ. Some states do not tax lottery winnings; others do. Federal tax on a large prize often lands in the top ordinary-income bracket, but itemized deductions, spreading annuity payments across years, and filing status still matter. The formula for the lump-sum case is Gross = 0.60 × Jackpot / Winners. For the annuity case, Gross = Jackpot / Winners. Tax = Gross × (t_federal + t_state). Net = Gross − Tax. If three people share a $500 million advertised jackpot and take the cash option under this 60 percent shortcut, each gross share is $100 million before tax. Use the calculator to compare sharing a ticket, to see how a high-tax state changes the cash option, or to understand why the advertised jackpot is not the amount wired to a winner. Do not treat 60 percent as a guaranteed cash factor; published Mega Millions cash values have been both below and above that round number. Annuity payments are typically annual, not a single check, and they may be assigned or prepaid only under limited rules. Consult the lottery, a tax advisor, and, for a real ticket, the official claim instructions before making a payout election.